Manufacture of reinforced glass



' To all whom it may concern: I

'terial, in which the adhesion of the cellulose ducing agent; for instance, an alkaline sulto use hard gelatin, i. e., gelatin which s vthus mechanically or chemically treated ad- In other words, it is highly desirable to one another in the presence of heat.

'not only to the surface of the lass, which ester or the like (with its surface treated does not offer any serious di culty when. -1nthe mannersp'ecified) against a sheet of .of-the gelatin to the lass (which has been 'glass, either uncoated or coated with gelatin,

:iED: STATES PA 'EINT GFFICE.

LEON rmn'cors mascm'r, or PARIS, rumor, ASSIGNOR 'ro soorn'rn DU vnm 'rnrrrnx, or rams, FRANCE.

manurac'rnnn' or nnmroncnn crass.

1 342,268 I Specification of ltetters l'atent. Patgn ted Jime 1, 1920, I

No Drawing. Original application filed March 21, 1914, erial No. 826,411. Divided and thie application I filed September 12, 1918. Serial No. 253,790..

p I tion of the problem which forms the subject Be it known that I, LEON FRA vgoIs of the present application consists in me- MASCART, a citizen of the. Republic of chanically or chemically treating the sur- France, residing ,at' 17. Rue Desnouettes, face of the sheet of cellulose ester before Paris France,.have invented a certain new it is brought into. adhesion with the gelatin. 6 and improved Manufacture of Reinforced 0 this end, the surface of the sheet of Glass, of which the following is a specificacellulose ester is slightly roughened. This tion. may be accomplished mechanically. by In the manufacture of glass strengthened means of a sandblast. Alternatively, it may or reinforced by an adherent sheet of cellube accomplished bysubjecting the surface '65 loid, cellulose ester, or other suitable maof the sheet to the chemical action of a reproduct, etc., to the glass is secured by an fid or any of the agents for denitrating intermediate layer of gelat1n,'itis important nitrocellulose. The sheet with its surface.

naturally hard or which has been artificially 'heres to a sheet of gelatin if the two sheets hardened, or tanned, or'rendered insoluble. are dipped'into alcohol and pressed against use gelatii n which can resist the destructive If, instead of using nitrocellulose or celaction 0 the moisture of the air and can luloid, sheets comprising a mixture of celluwithstand a large increase in temperature loid and cellulose acetate, such as are induswithout having a'tendency to melt-or run. trially prepared, be used, the same process The present invention relates to improveremains applicable. Sheets of cellulose ments in the method of making such an acetate, or other similar esters which do not article and in the article. itself, with special contain nitrocellulose, may be subjected to referenceto securing a perfect adhesion of the action of a hot'alkalin S l i nthe gelatin (whatever its nature and state) Instead of pressing a sheet of cellulose the gelatin is spread thereon but also to, gelatin, it is possible to effect substantially the surface-of the cellulose ester used with the same results by dipping the treated the gelatin as the strengthening medium. sheet of cellulose ester into a hot solution As hereinafter described, the adhesion of of gelatin and letting the. gelatin dry the gelatin to the glass isobtained in a very thereon. The thus coated sheet of cellulose simple manner by simply applying, in any ester, after it has dried, may be dipped into suitable way, a layer of an aqueous solution alcohol and pressed between two sheets of previously properly cleaned), and then 9.1- and in-the presence of heat.

lowing the gelatin to dry. The layer of In all the cases described a greatly iingelatin thus obtained can be hardened, proved adhesion between the celluloseester tanned,'or rendered insoluble by any of the and gelatin layers is secured, even whenwell-known :processes; for example, by the layers of gelatin and cellulose ester are treatment with bichromate of potash, forexceedingly thin. I malin, .etc. The chief difficulty heretofore Obviously, the process may be appliedto experienced, and which is overcome by the the manufacture of an article comprising present invention, relates to the securing but asingle sheet of glass reinforced on of a firm adhesion of this layer of hard one face or on both faces, or to a glass sandgelatin, which has been rendered insoluble, wichcomprising two sheets of glass with an to the cellulose ester usually forming the interposed reinforce of gelatin and 'cel lu main strengthening element of the struclose ester layers of the type described; or, ture. The problem may be solved in vaagain, to the manufacture of an article comrious ways, some of which, are set forth prising more than two sheets of glass, the

in 'my '00- endin application filed March several sheets being united and reinforced 21, 1914, erial 0.. 826,411, of which the in the manner specified. present application is a division. The solu- Glass prepared in the present manner has V a solidity and perfect adhesioii: between the faced by a layer of elements which compose it superior to that heretofore attained. If the gelatin has been suitably'h'ardened and rendered insoluble,

it resists the action of water and heat and can be used just as it is. The layer: of cellulose ester must not be too thin.

to form a sufficiently strong reinforce.

Finally, inasmuch as this reinforce is exposed either on its face or at its margins,

1t is important that it should be incombustible, and it is therefore advisable to make it of cellulose acetate.

I claim 1. As a new article of manufacture, re-.

inforced glass comprising a sheet of glass I gelatin adherent thereto, together with a layer .ofcellulose ester ad-.

herent to the gelatin, the face of the-cellu-' lose ester layer havl g a surface characteristic promoting the adhesion of the gela- 7 tin thereto.

"sion =ofgelatin thereto.

4. .As a new article of manufacture, rein- 2. As anew article of manufacture, rein? forced glass'comprising a sheet of glass ,faced by a layer of gelatinadherent thereto, together with a layer of cellulose ester adherent to the gelatin, the surface of the cellulose ester layer being roughened to prom0te the adhesion of the gelatin thereto.

8. As a new article of manufacture, reinforced glass comprising a sheet of glass faced by a layer of gelatinadherent thereto, together with a layer of cellulose ester adherent to the gelatin and having its surface chemically roughened to promote the adheforced glass comprising a sheet of glass faced by a layer of gelatln adherent thereto,

It must be at least.0.10.2 mm. thick. in order .of heat.

name to this specification.

together with a layer of cellulose esteradherent to the gelatin, the face of'the celluloseester layer having its surfaceroughened by a reducing agent to promote the adhesion of the gelatin thereto.

5. As a new article of manufacture, reinforced glass comprising a sheet of glass faced by .a layer of gelatin and a layer of cellulose 1 ester the layer of' cellulose esterface characteristic romotin gelatin thereto, the parts.

havlng a 'sur the adhesion of being united under pressure in the presence .6. In the process of making. glass reinforced by adherent'layers ofgelatinand cellulose ester, the step of alterlng the surface characteristic of the cellulose ester layer to promote its adhesionto thegelatin;

In the process of making glass reinand thereby 'promote the adhesion'of gela tin thereto. e

9. In the process of making glass reinforced by adherent layers of gelatin and cellulose ester, the step 'of.

mg agent in order to alter its surface characteristics' and thereby promote its adhesion to the gelatin. i 4

In testimony whereof I have signed my a LEQN FRAN oIs MASCART'."

subjecting the cellulose esterlayer to the actionof a reduc-' 

